When potassium nitrate is heated, it decomposes into potassium nitrite and oxygen. Write a balanced equation for this reaction and add the state symbols of the reactants and products.

Q. When potassium chlorate $\left(KCl{O}_3\right)$ is heated in the presence of manganese dioxide catalyst, it decomposes to form potassium chloride and oxygen gas. Represent this in the form of a balanced chemical equation.

Q.

Potassium nitrate on strong heating decomposes as under:
2KNO₃ $\stackrel{∆}{\to }$ 2KNO₂ + O₂
Calculate:
(i) weight of potassium nitrite formed.
(ii) weight of oxygen formed when 5.05 g of potassium nitrate decomposes completely.
(K = 39, O = 16, N = 14)

Q. Potassium chlorate $\left(KCl{O}_3\right)$ on heating gives potassium chloride and oxygen. Write a balanced for this reaction and indicate the evolution of gas.

Q. (a) When nitric acid is prepared by the action of concentrated sulphuric acid on potassium nitrate, what is the special feature of the apparatus used?
(b) Write the equation for the laboratory preparation of nitric acid from potassium nitrate and concentrated sulphuric acid.
(c) Potassium nitrate is prepared from potassium hydroxide and nitric acid. Name the type of this reaction.
(d) Which gas is produced when potassium nitrate is heated? Write the equation for the reaction. [5 MARKS]

Q. Describe your observations when potassium nitrate crystals are heated strongly in a test tube and a glowing splint is healed near the mouth of the test tube. Write a fully balanced chemical equation for the decomposition of potassium nitrate crystals.